1. Field of the Invention
The invention relates to a device with which both measurement of the alignment state and also measurement of vibration of a rotating machine are possible, and a method for determining a quality characteristic. The invention also relates to a device and a method for measurement of vibrations at a non-rotating part of a rotating machine.
2. Description of Related Art
Devices are known with which alignment, for example, of two shafts relative to one another can be measured. In machinery, motors, for example, drive pumps, the relative alignment of the motor with respect to generally heavier pumps has a major effect on the service life of the entire machine and its components. These devices contain an electronic evaluation device, a first optoelectronic transmitting and/or receiving unit and a second optoelectronic transmitting and/or receiving unit or a reflector instead of the second transmitting and/or receiving unit. These devices are described, for example, in U.S. Pat. No. 4,698,491 and U.S. Pat. No. 6,356,348 B1.
Moreover, devices are known with which vibration measurements are taken and to which an optoelectronic transmitting and/or receiving unit (hereinafter also called an alignment sensor) of an alignment device, as is described in the aforementioned patents, can be connected. In this case, in the past, the vibration sensor and the sensor of the alignment device had always been connected separately to the electronic evaluation device. These combined devices for alignment and for vibration measurement are available, for example, from the assignee of the present application under the trademark smartSCANNER®. Both alignment sensors, like the first optoelectronic transmitting and/or receiving unit and a second optoelectronic transmitting and/or receiving unit (which can also be omitted when using a reflector) as well as vibration sensors, can be connected to the electronic evaluation unit of the smartSCANNER. An inclinometer is contained in at least one of the two optoelectronic transmitting and/or receiving units.
These devices are suitable for taking both alignment measurements and also vibration measurements, but entail problems in reliable handling and in evaluation. When the machine is shut down, alignment measurements are taken. Afterwards, misalignment which may be present is corrected. These activities are often undertaken in a production shutdown, therefore, on the weekend or at night. After restarting the machine, it is a good idea to take a vibration measurement in operation.
As a result of more difficult working conditions at unusual times, it can happen that the optoelectronic transmitting and/or receiving units are forgotten on the shafts of the machine during dismounting and are damaged when the machine is started. Moreover, fatigued personnel often have difficulties in distinguishing or correctly assigning the directions for measurements of vibrations of the axial direction and vibrations of the radial direction in vibration measurement. This also applies especially when the personnel are not adequately trained or are fatigued. Furthermore, it is difficult to bring the corrected alignment which has been determined using the measurement device into agreement with the vibration picture. Also, data which enable this assignment, such as tolerance data or reference spectra of vibration pictures, are often contained in extensive databases which are stored on remote computers and whose contents are not available at all to personnel at the facility at the time or cannot be easily found.
Another problem is the different electronic components which are required for vibration measurement devices and alignment sensors for the evaluation of the signals of vibration sensors, optical position detectors and inclinometers before the signals can be further processed in the central processor of the electronic output unit.